If someone asked me what my favorite perennial was, I could only say that it changes with each passing year. This year the answer is the hardy geranium, known around these parts as the Cranesbill.My fascination with hardy geraniums has grown steadily as I have discovered the countless varieties that exist. In European gardens they are as common place as phlox is in American perennial gardens.
Most of us think of geraniums as an annual that we plant in our yards or in pots to add color to our patios during the summer months. This plant is actually a Pelargonium. The confusion over the name can be attributed to the father of modern taxonomy, Carl Linnaeus, who insisted on lumping Geranium and Pelargonium into one ‘Geranium’ category. Over time the term was only associated with pelargonium and the true geranium lost its popularity (and identity).
The true geranium is a perennial. You can see the wild forms covering the floor of wooded areas in the springtime, but my favorites are the cultivated varieties that I first became familiar with on European garden tours. I’ve been told that they are the easiest perennial to grow. From my experience, so far, I agree.
The primary point here is that there are hundreds of varieties of hardy geraniums and a size and form for every location in your garden so seek them out. The two most common hardy geraniums in this area are Geranium ‘Johnson’s Blue’ and G. sanguineum, or ‘Bloody Cranesbill’. ‘Johnson’s Blue’ has an airy mass of finely cut foliage and a healthy spray of lavender-blue blossoms that are one of the first to appear in the spring. With dead-heading ‘Johnson’s Blue’ will bloom sporadically throughout the summer. In the fall the foliage turns a red color before dying back. Cut the foliage down to ground level like you would with most herbaceous perennials.
‘Bloody Cranesbill’ is a mound forming hardy geranium that is covered with fuchsia-pink blossoms by early summer. In a four year period of time our ‘Bloody Cranesbill’ has grown to about two feet in diameter.
Some varieties of hardy geranium are used as border plants, others as centerpieces of the garden doing well in the foreground of other taller growing perennials like phlox. G. psilostemon can mound to the size of a small bush if it’s happy. The miniatures, or alpine varieties, of hardy geraniums can be used as border plants because their growing habits are low and spreading. Try the alpine variety G. cinereum ‘Ballerina’ if you have areas with gravel or rocks.
For dry, sunny locations G. malviflorum (and that is its common name!) is best suited. It likes to trail out and if it is given a ledge to cascade over it provides a dramatic effect. But, you must interplant with other geraniums or summer perennials because it dies back after its blooms are spent. New growth appears in the fall and provides green foliage throughout the winter.
There are also varieties for dry, shady areas. G. macrorrhizum ‘Bevan’s Variety’ and ‘Ingwersen’s Variety’ provide rosy-red and light pink blossoms, respectively. In shady areas under trees many people like a more naturalized look and G. phaeum is perfect for this. It is an excellent ground cover and gives a show of deep-red blooms in the spring, the rest of the season you have a healthy mass of green foliage.
The Perennial Plant of the Year from a couple of years ago was Geranium ‘Rozanne’ is a knockout. Give it a good garden site with some shade from the hot afternoon sun and you will enjoy white-tinged violet blooms all summer long.